Wang Yonghong, Gao Wenkang, Wang Shuai, Song Tao, Gong Zhengyu, Ji Dongsheng, Wang Lili, Liu Zirui, Tang Guiqian, Huo Yanfeng, Tian Shili, Li Jiayun, Li Mingge, Yang Yuan, Chu Biwu, Petäjä Tuukka, Kerminen Veli-Matti, He Hong, Hao Jiming, Kulmala Markku, Wang Yuesi, Zhang Yuanhang
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China.
China National Environmental Monitoring Center (CNEMC), Beijing 100012, China.
Natl Sci Rev. 2020 Aug;7(8):1331-1339. doi: 10.1093/nsr/nwaa032. Epub 2020 Feb 28.
Although much attention has been paid to investigating and controlling air pollution in China, the trends of air-pollutant concentrations on a national scale have remained unclear. Here, we quantitatively investigated the variation of air pollutants in China using long-term comprehensive data sets from 2013 to 2017, during which Chinese government made major efforts to reduce anthropogenic emission in polluted regions. Our results show a significant decreasing trend in the PM concentration in heavily polluted regions of eastern China, with an annual decrease of ∼7% compared with measurements in 2013. The measured decreased concentrations of SO, NO and CO (a proxy for anthropogenic volatile organic compounds) could explain a large fraction of the decreased PM concentrations in different regions. As a consequence, the heavily polluted days decreased significantly in corresponding regions. Concentrations of organic aerosol, nitrate, sulfate, ammonium and chloride measured in urban Beijing revealed a remarkable reduction from 2013 to 2017, connecting the decreases in aerosol precursors with corresponding chemical components closely. However, surface-ozone concentrations showed increasing trends in most urban stations from 2013 to 2017, which indicates stronger photochemical pollution. The boundary-layer height in capital cities of eastern China showed no significant trends over the Beijing-Tianjin-Hebei, Yangtze River Delta and Pearl River Delta regions from 2013 to 2017, which confirmed the reduction in anthropogenic emissions. Our results demonstrated that the Chinese government was successful in the reduction of particulate matter in urban areas from 2013 to 2017, although the ozone concentration has increased significantly, suggesting a more complex mechanism of improving Chinese air quality in the future.
尽管中国在空气污染调查与控制方面已投入大量关注，但全国范围内空气污染物浓度的变化趋势仍不明确。在此，我们利用2013年至2017年的长期综合数据集，对中国空气污染物的变化进行了定量研究，在此期间，中国政府在污染地区大力减少人为排放。我们的研究结果表明，中国东部重污染地区的PM浓度呈显著下降趋势，与2013年的测量值相比，每年下降约7%。测量到的SO、NO和CO（人为挥发性有机化合物的替代物）浓度下降，可以解释不同地区PM浓度下降的很大一部分原因。因此，相应地区的重污染天数显著减少。北京城区2013年至2017年测量的有机气溶胶、硝酸盐、硫酸盐、铵盐和氯化物浓度显著降低（这将气溶胶前体的减少与相应的化学成分紧密联系起来）。然而，2013年至2017年，大多数城市站点的地表臭氧浓度呈上升趋势，这表明光化学污染加剧。2013年至2017年，中国东部省会城市的边界层高度在京津冀、长江三角洲和珠江三角洲地区没有显著变化趋势，这证实了人为排放的减少。我们的研究结果表明，尽管臭氧浓度显著增加，但中国政府在2013年至2017年成功降低了城市地区的颗粒物浓度，这表明未来改善中国空气质量的机制更为复杂。
